Answer / s. kanniyappan

The measuring the difference between HP and LP of a process
will give dp.

By connecting a pressure source with t-off to master gauge
to the HP side and venting the LP side to the atmosphere,
varying the pressure according to the range and measuring
the mA in series and adjusting zero and span according to
the variation.

In case of of Dry leg connecting a pressure source with
t-off to master gauge to the LP side and venting the HP side
to the atmosphere, varying the pressure according to the
range and measuring the mA in series and adjusting zero and
span according to the variation.

Answer / senthil

CALIBRATION OF A DP TRANSMITTER VARIES DEPENDING ON ITS
RANGE ( POSITIVE OR -IVE TO +VE)
FOR EXAMPLE:IF THE RANGE IS 0 TO 10BAR IS THE RANGE-
U HAVE A FIVE WAY MANIFOLD ON THE
TRANSMITTER.THE POSITION SHOULD BE
- VENT VALVE TO BE CLOSED
-LP ISOLATION VALVE IS OPENED AND VENT TO ATM
- CONNECT THE CALIBRATOR(DRUCK OR HYDRAULIC PUMP) ON THE HP
ISOLATION.
SINCE OUR RANGE IS OF POSITIVE VALUE.WE APPLY CORRESPONDING
PRESSURE ON THE HP SIDE..0,2.5,5.0,7.5,10

FINALLY DONT FORGET TO CONFIGURE IT AS SQUARE ROOT USING
HART COMMUNICATOR IF WE USE IT FOR A FLOW MEASUREMENT..

Answer / amith.patil17@gmail.com

Differential pressure Can be simply measured by DP
transmitter which is connected to the two tapping point
with difference in pressure in both points this DP is
connected after the Threeway manifold valve whose advantage
to calibrate the transmitter on the site by opening the
middle valve so that to get 4mA,else this Pressure change
in level or the flow causes the material dimension change
which material is connected to transmitter which acts as a
resistance to a wheatstone bridge which generates rhe
corresponding current which is transmitted to the control
room.

Whether the DP transmitter can be utilised in the medium of Vaccum for the measurement of Level?

10 Answers  

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please send me some question papers of HPCL aptitude test ?? please send it to bipinb.28@gmail.com ...

0 Answers   HPCL,

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calibration of instruments.

11 Answers   ONGC,

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How many ohms are required for proper earthing?

0 Answers  

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why generation of syncronized generator increases when frequency of grid is less then 50Hz & generation decreases when grid frequency goes up from 50 Hz, as comparision with set value entered in govering panel?

1 Answers  

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In 2 wire transmitter 1 wire is used for power and other is used for signal( 4-20)ma In 4 wire transmitter 2 wires are used for power and 2 wires are used for signal (4-20)ma . but my question is "what is the criteria or parameters we have to consider while selecting these transmitters for eg( distance, safety zones etc.

1 Answers  

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What is the difference between mmwc and mmwg?

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A motor is taking 15 Amps at no load and 60 Amps at full load. and a valve has to open 10% at full load and 80% at no load. How to draw ladder logic.(PLC).

2 Answers  

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i feel sq. pipe is better than round pipe pls give comment for this. advance thanks for reply

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why we use casced loop

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what is a half wave, full wave, and bridge rectifer.

0 Answers   Takreer,

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what difeerent between HART and BRAIN?

3 Answers  

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